There's a thread elsewhere started by someone complaining about sound quality in a factory (HO) loco and the overwhelming majority of replies and questions are only focusing on what type of speaker was used and what type to replace it with. Any mention or questions about speaker enclosures doesn't seem to get anyone's attention very well and remains mostly unanswered. Why is this still such a widely-misunderstood or even cast-aside factor...seemingly in both custom and even some factory sound installs? I know John C., Steve R. and others here have certainly done more than there part to try to get the word out here at TRW. it's frustrating that a seemingly large number of hobbyists and perhaps even some manufacturers remain unaware of how good the sound can actually be, which also can't be very good for the DCC sound market.

I don't get it either. Speaker/enclosure design principles aren't a secret. I've been posting on how to do this since 2013. I haven't kept anything "private" - it's all in the public domain for anyone to see and copy.

But to be fair to the manufacturers, I think a major part of the problem is designing something that can be produced and assembled efficiently. That often means that the enclosure gets short-shrift, because making one like I do for my installations, or even using 3D printing (a la John LeMerise) for the enclosure, followed by hand-wiring the speaker, gluing it to the enclosure, and then hand-soldering the speaker wire connections to a decoder, just isn't going to cut it for an assembly process.

On the other hand, I keep thinking that if you're going to charge $150 for a sound-equipped diesel, why not charge $175 and get it right. And when it comes to steam, there really is no excuse - the tender has plenty of room; the speaker will be hand-wired anyway; and the loco already costs north of $300, so charge $25 more and make it sound as good as it can.

I guess part of it is also poorly-informed consumers. Some folks hear a shrill, no-body-to-the-sound factory install, and think "This is GREAT! I HAVE SOUND!" They have no idea that the sound they are hearing is terrible in comparison to what it could be, so they don't demand better performance from the manufacturers.

I do think some of the manufacturers "get it" - my Atlas SD35 sounds pretty darn good. My IM SD40-2 wasn't as good, but IM at least seems to be trying. The steam manufacturers are hopeless. The crap I've taken out of Bachmann, BLI and even Athearn steamers isn't worth 10 cents. Why even do it if you're going to do it that poorly?

My response is just to keep posting here, hope manufacturers read some of it, and hope that consumers will demand better.

I was so pleasantly surprised at how well Atlas did with the speaker design/enclosure on the SD35. I had expected something that would have to be reworked and "Colombo'd" to make it better. Even nicer is that the Atlas Silver engines come with the speaker already installed.

Alas, Scale Trains just didn't seem to understand it with the Tier 4's. I hope that changes.

Because the vast majority of people don't understand acoustics--and this includes manufacturers, regrettably. Audiophiles--even casual ones--know this intuitively. But the rest... we will need to educate them. It's not their fault, either, so it requires a degree of patience.

(This, from someone who can't stand model sound--but worked as an audio engineer, so yes, I understand the problem all too well.)

I couldn’t agree more with everyone on this thread.The enclosure is as important if not more important than the speaker itself for good sound.That being said a crappy speaker will always be a crappy speaker but will sound less crappy in a good enclosure.The enclosure doesn’t have to be a mere rectangular box either; stepped enclosures, offset enclosures, extra long and shallow enclosures etc can all help with the aim to achieve the desired enclosure sweet spot volume for the speaker being used in the space you have does make better sound.

To my ear and after experimenting on this, those sweet spot volumes are for me at least:-8x12 speaker = 500mm39 x 16 speaker = 750-800mm3

I know John C has used some bigger speakers that I have not ( my modeling era is all diesel) but I believe IIRC an 18 x 13 needs about 1000mm3.

Also, on a split frame loco with a tank installed speaker, shooting the sound into the shell sounds better than shooting the sound down to the track.

Because the vast majority of people don't understand acoustics--and this includes manufacturers, regrettably. Audiophiles--even casual ones--know this intuitively.

That's exactly what I was going to write.Remember all the youths in the '70s riding around in their souped up cars with couple of 6x9" speakers sitting (magnet down) on the package shelf under the rear window, playing loud distorted crappy-sounding music? Well, these are the same people now designing sound-equipped models. They just do not understand acoustics.

Speaker and its enclosure is an inseparable pairing which should always be considered that way.

That's exactly what I was going to write.Remember all the youths in the '70s riding around in their souped up cars with couple of 6x9" speakers sitting (magnet down) on the package shelf under the rear window, playing loud distorted crappy-sounding music? Well, these are the same people now designing sound-equipped models. They just do not understand acoustics.

Speaker and its enclosure is an inseparable pairing which should always be considered that way.

Oh yeah, I remember doing just that in those days as I was one of those youths in the ‘70’s. Loud and even louder was what mattered along with those Starsky and Hutch or Ralle go-faster stripes on the car.. 😀

Not to hijack the thread (too much), but I could say the same, once again, for sound design. I remain convinced that the soundfile designers are taking wave files that sound good in their headphones and uploading them to the decoders without further consideration. EQing the source sounds appropriately for the speaker they'll actually be played on probably also contains some unrealized gains in quality. Probably less so than speaker enclosures, but something nonetheless.

Not to hijack the thread (too much), but I could say the same, once again, for sound design. I remain convinced that the soundfile designers are taking wave files that sound good in their headphones and uploading them to the decoders without further consideration. EQing the source sounds appropriately for the speaker they'll actually be played on probably also contains some unrealized gains in quality. Probably less so than speaker enclosures, but something nonetheless.

Spot on! The sound can easily be "tuned" to take best advantage of the speaker and enclosure for the best response. But is that done? I rather doubt it.

Not to hijack the thread (too much), but I could say the same, once again, for sound design. I remain convinced that the soundfile designers are taking wave files that sound good in their headphones and uploading them to the decoders without further consideration. EQing the source sounds appropriately for the speaker they'll actually be played on probably also contains some unrealized gains in quality. Probably less so than speaker enclosures, but something nonetheless.

Spot on! The sound can easily be "tuned" to take best advantage of the speaker and enclosure for the best response. But is that done? I rather doubt it.

I've wondered about this too....bringing the lower tones up some more so that the smaller speakers can play them better. I have a few LokSound files installed, particularly a couple GE sound files, where the throaty glug, glug of the prime mover sounds really great. Meanwhile, the EMD prime mover rumble in other files is not reproduced nearly as well or at all...at least not with a 9x12 speaker. It sure seems like one could bring the EMD rumble up closer to whatever level the GE glugs are and you could have something that sounds way better.

I've wondered about this too....bringing the lower tones up some more so that the smaller speakers can play them better. I have a few LokSound files installed, particularly a couple GE sound files, where the throaty glug, glug of the prime mover sounds really great. Meanwhile, the EMD prime mover rumble in other files is not reproduced nearly as well or at all...at least not with a 9x12 speaker. It sure seems like one could bring the EMD rumble up closer to whatever level the GE glugs are and you could have something that sounds way better.

This is the one area where Soundtraxx beats ESU. The Tsunami decoders have a built-in 7 band equalizer that you can use to fine-tune the sound to your heart's content. But understand that the small speakers we use simply cannot produce sound below about 300hz. It doesn't matter what the factory spec sheet says; acoustic output for these speakers falls off a cliff after 500hz, and is basically gone after 300hz. So there's only so much one can do with EQ - at some point, physics plays a part . . .

John C.

PS - but for the equalizer, there is nothing ELSE about the Tsunami that I like in the diesel versions. The steam versions are pretty good, and but for my desire to have only one brand of decoder, I'd probably still use the Tsunami 2 in steam installations.

This is the one area where Soundtraxx beats ESU. The Tsunami decoders have a built-in 7 band equalizer that you can use to fine-tune the sound to your heart's content. But understand that the small speakers we use simply cannot produce sound below about 300hz. It doesn't matter what the factory spec sheet says; acoustic output for these speakers falls off a cliff after 500hz, and is basically gone after 300hz. So there's only so much one can do with EQ - at some point, physics plays a part . . .

John C.

PS - but for the equalizer, there is nothing ELSE about the Tsunami that I like in the diesel versions. The steam versions are pretty good, and but for my desire to have only one brand of decoder, I'd probably still use the Tsunami 2 in steam installations.

But the actual sounds could instead be equalized by the sound project creator (before compiling them into a sound project). So no equalizer in the decoder would be needed. Plus as I understand, the equalizer in Tsunamis modifies all the sounds equally, so it changes the sound of the chuffs, whistle, bell, and all the other sounds. Equalizing the individual sounds in the sound project seems like a more desirable way to enhance the decoder's sounds. We just have to get the sound project designers to start doing that. Yes, I understand that there are all sorts of different speakers and enclosures out there, but I think that a basic boost of the lower frequencies (not enough to cause distortion) would be beneficial for all speakers.

But the actual sounds could instead be equalized by the sound project creator (before compiling them into a sound project). So no equalizer in the decoder would be needed. Plus as I understand, the equalizer in Tsunamis modifies all the sounds equally, so it changes the sound of the chuffs, whistle, bell, and all the other sounds. Equalizing the individual sounds in the sound project seems like a more desirable way to enhance the decoder's sounds. We just have to get the sound project designers to start doing that. Yes, I understand that there are all sorts of different speakers and enclosures out there, but I think that a basic boost of the lower frequencies (not enough to cause distortion) would be beneficial for all speakers.

Agree - selective equalization, particularly of the prime mover, could improve the sound we get. The problem is that you have to aim for "middle ground" because HO installations can use much larger speakers than N scale ones. You COULD have separate sound files with different EQ for different speaker sizes - it actually wouldn't be that hard to do, but I suspect that customer confusion would be a worry.

Open-back dipole designs with regular basket/cone speakers are rare (as opposed to flat-panel speakers like electrostats, which are always dipoles), but in the audiophile world they try anything to differentiate products. And properly set up (with the correct distance from the rear wall to bounce the rear sound wave), dipoles work and can have a particularly-enveloping sound. My own speakers are dipoles. Magneplanar 1.6QR's (photo is of 1.7's):

[ Guests cannot view attachments ]

I love my Maggies, but I don't think dipoles are the way to go for N scale diesels or steam tenders . . . - although . . . Magneplanar DOES make desktop speakers these days . . .